you mention that Reb Moishe and R"Yona seem not to agree. Reb Moishe seems to completely ignore the R"Yona, perhaps you can elaborate. I am particularly interested in this Sugya, a little bit Halocha LeMaseh, but for the present just being Mefalpel; if could you point me in any direction I'd be most grateful.
meir rabi, australia
[This response should not be construed as a Halachic ruling on the question. Rather, it is an exploration of the topic to help our readers become more familiar with the issues involved.]
The contemporary Poskim are indeed perplexed by this R' Moshe (see R' Tzvi Weber Shlit"a's comments at the end of the first volume of the Sefer Lerei'acha Kamocha, and on pg. 102). One who closely reads through R' Moshe's Teshuvah (O.C. 2:51, especially at the conclusion) will note that R' Moshe himself was not 100% certain that this was the correct Halachic conclusion, and only used it as a leniency in a pressing situation.
All the best,
[I hope this response has clarified the issue. For all practical questions on the issue, please consult your local Orthodox rabbi.]